The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingDisassembly
Remove park/neutral position switch assembly
Remove the nut, washer and control shaft lever.
Using a screwdriver, pry off the lock plate.
Remove the nut and lock plate.
Remove the 2 bolts and pull out the switch.
Remove breather plug hose
Remove oil coo ...
Short in front passenger side squib circuit
Description
The front passenger side squib circuit consists of the center airbag sensor
and the front passenger airbag.
The circuit instructs the srs to deploy when the deployment conditions are met.
These dtcs are recorded when a malfunction is detected in the front passenger
side sq ...
Transponder chip malfunction
Description
This dtc is output when: 1) during key code registration, a key malfunction
occurs; 2) the key code was
unable to be registered properly.
Inspection procedure
Reregister key
Clear the dtc (see page ei-18).
Reregister the key code with the transponder key ecu
(s ...